BLUEMOMENT

Those with the 10" drum Rotostay furler (probably with 8mm forestay) need to check that the water escape holes at the bottom of the foil are clear. The only maintenance this furler ever got or required was some graphite grease poked into the drum cavity; but, eventually, the grease travels up to the start of the foil and blocks the (quite small) water escape holes - or else the wee holes just get gummed up. Come winter time and water starts collecting in the bottom foil. If it freezes, the foil expands and is thereafter useless; the halyard swivel is seized.

This could apply to a few other, older, furlers.

ho hum ...

Well said sir. I'm in the throws of trying to fix a friends furler (SBRR is the only indication of maker) and noted that when we got it down and started playing, water was pouring out of the foil. In this case there were no drain-holes at the bottom, and I suggested it would be good to have one, but I hadn't fully appreciated the potential disaster of a freeze-up.
I guess my Balmar drains down the forestay duct and this only applies to those types with a rotating forestay between two bearing assemblies (and the genny halliard wire brought back down to the drum?)